The Dyson founder notably created 5,127 prototypes of his Dual Cyclone bagless vacuum cleaner before striking gold. It would become the foundation of his 21-year-old company. In addition to constantly innovating and iterating on appliances customers use every day -- from vacuums to fans and hand dryers -- Dyson and his team have also been at work on some fairly prescient gadgets many people have never seen.

Back in 2001, Dyson built a prototype called the Dyson Halo, a portable digital headset that would allow the user to check their e-mail, use applications and get help from a virtual assistant. His precursor to Google Glass also included some now-familiar hardware, including a smartwatch-esque wrist controller. Dyson also invented an automobile engine that could filter out environmental toxins, along with a digital motor. While none of these inventions have made it to market, it hasn't stopped the entrepreneur from recently investing $8 million in a robotics lab and ponying up $420 million to expand its R&D facility.

Dyson is also passionate about helping engineers and scientists find their way and started his James Dyson Foundation to encourage the talent and education of inventors and problem-solvers in the making, whether they’re high level graduate students or second graders.

We caught up with Dyson to talk about throwing out the playbook, the importance of weighing your options and fighting for your ideas.

Q: Knowing what you know now, what would you have done differently when you were first starting up?A: I would have fought harder to protect my ideas from day one.

Q: How did you learn this lesson?A: When I first invented the bagless vacuum and tried to find a company to manufacture it, I was laughed off stage again and again. So when a company finally showed interest, I immediately jumped on a plane to sign the deal. By the time I arrived, they had completely changed the terms and had me signing documents I knew to be unfair. I felt backed into a corner, but I thought it still could be my big break. So I accepted the deal. A few months later I handed over my engineering drawings. They went ahead and made my vacuum without me, then sued me for fraud. It took all my energy and nearly every penny I had to fight to get my designs back, so I could actually sell the invention that was rightfully mine.

Q: What do you think would have happened if you had had this knowledge then?A: I would have spent my energy and money on finding a way to make the machine myself, rather than traipsing the globe trying to convince others to believe in my technology. More importantly, I would have saved myself a lot of time by patenting my designs from the start, despite how arduous and costly the process was. Regrettably, it’s the only way for inventors to protect what’s rightfully theirs.

Q: How do you think entrepreneurs might benefit from this insight?A: When you’re a penniless inventor, engineer or entrepreneur, it’s tempting to fall for the first cash offer. But more often than not, a better offer will come. Better than that, I always try and persuade inventors to hang onto their technologies with a view to commercializing them themselves. It can be a long road but an invention that works better is worth fighting for.

Q: Besides invent a time machine, how might they realize this wisdom sooner?A: The important thing is to remember why you started down this road. Ideas worth investing that much time and energy on are likely worth defending and shouldn’t be compromised. But the education behind inventing is much stronger now than it was when I was at a university.

Q: What are you glad you didn't know then that you know now?
A: Being young and very naïve is a necessary ingredient for success. You aren’t bogged down by the weight of your experience, which can inhibit your willingness to challenge the norm. There were many times when good sense told me to give up. Somehow, dogged pride and determination carried me through. That’s why I continue to hire recent graduates -- they don’t do things by the book. They’ve never even read the book.

Q: Best advice for aspiring entrepreneurs?A: Never be afraid to fail. I spent years in my toolshed building thousands of prototypes of my bagless vacuum. Each one was a failure. Until finally there was one that wasn’t. Today, Dyson has 1,500 engineers doing the same thing: trying, failing, reworking and trying again. It’s the only way to make something that works.

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